Breech bolt retracting means



pril 15, 1947.

F. W.. SAMPSON ET AL BREECH BOLT RETRACTING MEANS Filed May 1, 1944 44- gaa/uvm FREDERICK W. `EAM P513 N,

33 afmv far/WL@ @www Patented Apr. 15, 1947 J..Hyde, Brooklyn, N. Y.. assignors to General Motors Corporation, a corporation of Dela- Wale Application May 1, 1944, serial No. 533,568

4 Claims.

This invention relates to an improved breech retracting means fora iirearm having afreciproeating breech member and more particularlyv to such means suitable for application to a firearm of the type commonly referred toas a submachine gunformachine pistol.

`It is the primary object of this invention to produceva. dependable breech retractingmeans which does not partake of movement of thebreech member during `automaticiire and does not therefore have any exposed moving parts which might injure hands `or clothing or detract from the eili- ,ciency of the Vweapons operation in confined spaces or in heavy undergrowth.

Itis-1a' further object to provide a breech retractingi system for rearms which may be mountedand Awhich can be operated 'without necessitating the provision of openings `or* slots in the wall oflthe rearm which can be obstructed' by dirt or foreign material. The exact nature .of the inventionY as -well `as other objects and advantages thereof will be clearly apparent from an examination ofthe following specincation referring to drawing in which:

. Fig. 1 is a partial, Vlongitudinal` sectionalview through a rearm embodying our invention;

Figs. `2 and 3 are partial longitudinal sectional views taken in the same plane as Fig. 1 but showing the mechanism indifferent stages of operation;`

Fig. 4 is anlenploded` pictorial view of the parts making Jup the cooking mechanism;

Fig. 5 is a cross sectional view on the linez-- of Fig. 1.

Fig. 6 isa cross-sectional view on lline 6 6 of Fig. 1.

. `Referring `to the drawing by characters of reference it will be seen that the firearm shown therein is of the same general type as that disclosedin our copending applications for U.. S. Lettersf Patent bearing .Serial Nos. 533,566; 533,567; 5331.569 ;and53.3,570, led May l, 1944, ini which the annexed the structure disclosed but not claimed in this application is claimed, and comprises a receiver I having mounted therein a reciprocating bolt ID. The construction shown herein `mounts the bolt lil onspa'ced guide rods l5 surrounded bydriving springs l1 which impel the bolt forwardly into battery position. The particular retracting means to be described hereinafter is not however limited to this construction as it is applicable to the problem of retracting any reciprocating member.

A drawn sheet metal housing 44 is shaped to conform to the exterior contour of the receiver and is lprovided at its front end with a tongue 45 engaging Va slot in the magazine housing 3 and at its rear end with a tongue 46 engaging a slot in the lower portion of the receiver. Matching apertures 4l and 48 are provided in the housing lili and in that portion of the receiver opposed thereto. The trigger guard i9 is formed of resil- V ient material and is provided with shoulders .49a

which will not pass through the matching apertures 41 and 48 and with an arched tongue.V 5D which does pass through the apertures intolcontact with the inner wall of the receiver. `It will be apparent that when the trigger guard is bent upwardly against its own resiliency into a position in which the tongue 5I may snap into an aperture 2a in the grip portion of the receiver that the housingwillbe securely retained in place. It will be noted that the side walls of the housing over;- lap the side walls of the receiver and thatV the lower housing forms a complete closure for the openings in the lower portion of the receiver. In addition to serving .as a closure for the lower part of the receiver the housing forms a support for-the retracting mechanism, to be described in detail below and the ejector 52 which is riveted or otherwise secured thereto and extends upwardly into a, position vto be received in a groove 53 in the bolt in position to engage the head of a cartridge gripped by the `extractor and impel same upwardly andfto .the right as the bolt recoilsupon firing. A stop tongue 54, cooperating with the'retracting mechanism in a manner to be described hereinafter, it cut from the rear edge of the ejector and turned inwardly acrosslthe housing.

A beech-retracting handle 55 is provided with an axle 55a pivotally mounted in the lower portion of the housing 44. Within the housing a portionof the axle isflattened and carries thereon a torsion spring 56 and a retracting leverarm 5T iwhich so engages the flattened portion 'of the axle thatit is :constrained to rotatetherewith;

and under the innuence oi the'spri'ng 56 boththe handle and the retracting lever arm tend to-swing forwardly `in the direction of the magazine housin position to engage the heel 6| of the pawl and prevent damage to the spring in the event of displacement of the retracting handle from its idle position during intervals when the housing may have been removed from the receiver. It will also be noted that the heel of the pawl engages the arched cam surface 44a as the retracting lever arxn nears its forward position, thus rocking the pawl downwardly and to the rear about its pivot. Obviously in order to accomplish this Vresult the spring 56 will have to be capable of exerting greater force than the spring 59. This camming action positively removes the pawl from the path of the bolt during automatic operationof the arm. The tongue 54 on the ejector extends across the path of the pawl and aids the cam surface 44a in removing the pawl from the path of the bolt and in preventing the pawl from assuming a position in which improper assembly might be possible when the housing is attached to the receiver.

As the reti-acting handle is swung rearwardly against the action of the spring 56 the spring 59 will urge the pawl upwardly into the groove 62 in the lower face of the bolt and into a position in which the toe 63 of the pawl engages a depression E4 in the rear end of the groove. Further retraction of the handle will result in carrying the bolt `rearwardly with the pawl into a position in which the Sear 26 engages and retains the bolt. Releasing the retracting handle will permit the handle, lever arm, and pawl to return to their inactive forward position in which there is no connection with the bolt and in which position the cooking mechanism may remain until such time as it is again necessary to cock the mechanism manually. It will be noted that the mechanism shown herein does not present any exposed parts which partake of movement of the bolt during automatic re and that there is therefore no danger that hands or clothing will be injured during automatic fire. At the same time however, there is provided a most convenient cooking handle which by an easy natural movement will engage itself with and cock the mechanism.

i Itwill also be noted that this mechanism functions Without requiring the provision of openings, slots, or track guided members which might permit the entrance of dirt into the interior mechanism or which might in themselves be obstructed by dirt or foreign materials.

Although this mechanism finds its greatest utility as a breech retracting means for an automatic firearm it will be obvious that similar means might be applied to the intermittent manual operation of any reciprocating member.

We claim:

1., In a firearm, the combination of a reciprocating firearm member, a lever journaled in the firearm, a pawl member having a pawl portion and an `extensionV portion in longitudinal alignment therewith, means intermediate said portions pivotally mounting said pawl member on said lever, means causing said pawl to engage the firearm member when the lever is actuated in one direction and means engaging said extension portion when said lever is moved in the reverse direction whereby said pawl is drawn clear of the path of the firearm member. Y

2. A firearm cooking mechanism comprising a housing, a lever journaled in the housing, means to swing the lever, a pawl member having a pawl portion and an extension portion longitudinally in alignment therewith, means intermediate said portions pivotally mounting said pawl member on said lever, a spring abutting sa'id lever tending to bias the same to an idle position, Spring means Vtending to swing the pawl member toward a position in substantial prolongation of the lever, and means on the housing engaging said extension portion as the lever approaches its idle position to cause said pawl portion to assume a pivoted back position on the lever when the levez` is in idle position.

3. In a firearm, the combination of a member to be cocked, a housing, a crank, a spindle fixed to the crank and journaled in the housing, a lever arm within the housing and engaging the spindle to be rotated thereby, a spring engaging the housing and the lever arm and tending to bias the crank and the lever arm t0 a forward idle position, a pawl member having a pawl portion and an extension portion in longitudinal alignment therewith, means intermediate said portions pivotally mounting said pawl member on said leverarm, spring means engagedbetween the pawl portion and the lever arm and biasing the pawl member toward a position for engagement with the member to be cocked, andfmeans on the housing engaging said extension portion when the lever is in idle position to hold the pawl portion away from engagement with the member to be cocked.

4. In an automatic rearm, the combination of a reciprocating firing member, a cooking mechanism therefor including a pawl member having a pawl portion and an extension portion inlongitudinal alignment therewith, a crank means operatively connected to said pawl member intermediate said pawl portion and said extension portion, means causing said pawl portion to engage said firing member to cock the same when the crank means is moved in a rearm cooking dlrection, and means arranged to engage said extension portion to remove said pawl portion from the path of said firing member when said crank means is moved in a direction opposite to said cooking direction to a non-operating position.

FREDERICK W. SAMPSON. GEORGE J. HYDE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PA'I'ENTS Y Date German Feb. 7, 1924 

